1. Field of the Invention
The present invention relates to a storage medium stored with a program for generating a group of objects displayed for a video game, an object displaying method and a game apparatus.
2. Description of the Prior Art
Recently, video games in which sophisticated technologies are used are being developed. In these games, display objects (hereinafter, referred to as object for simplification) such as persons, machines, tools, buildings and backgrounds, etc. positioned in a three-dimensional space are displayed on a display and the objects are moved in response to a player""s operations. Each object is represented as a collective of a plurality of polygons and an image including a plurality of objects is generated. In video games, the image generation process is repeated several tens of times a second, several tens of static frame images (hereinafter, each static image will be referred to as frame image) are generated.
Recently, in addition to characters, the contents of images are also being displayed full of variety. For example, not only static objects such as mountains, ground or buildings, etc. but also objects which move over time such as waterfalls or clouds are displayed or, sometimes flying objects such as birds are also displayed.
The movement of objects comprising images are full of variety, and generation conditions, generation position requirements, movement mode, display duration of the objects, and data used to generate images representing respective objects are different depending on each object. For example, to represent the changes of postures of a bird character, it is necessary to move a plurality of joints which compose the character, and as with a player character or an enemy character, motion data is used to represent its movement.
It is desirable that a waterfall is displayed so that the flow of water or splashes change as time passes. That is, generation conditions are specified with respect to the waterfall and when the conditions are met, the object is generated. Sometimes generation position is also altered randomly over time.
It is desirable that clouds are displayed by dynamically changing images so that they are generated over time, and generation positions are changed randomly over time, or they disappear over time, moreover, their configuration is changed over time.
In conventional arts, in order to generate an image of a variety of objects to be displayed on the screen, for each object, an object image generation program for generating an image of the object is used. This program generates, moves or extinguishes the object in accordance with the image requirements such as generation conditions, generation position, movement mode, color and data to be used with respect to the corresponding object, and generates images representing objects which have been generated or moved. As images for each object are generated, input data to be given to the corresponding object image generation program are different depending on each object.
In a conventional art as described above, a plurality of object image generation programs for generating a plurality of different objects are loaded at a time in the main memory (generally, this is known as random access memory (RAM)) contained in a computer within a game apparatus, and executed. For executing each program, a work area for each program is secured and used within the RAM.
In recent video games, the total number of objects to be used is large, and it is very possible to increase their number. As a result, the capacity of RAM actually required for the object image generation program will become larger and it is still very possible to increase it from now on.
On the other hand, recent games are coming to use larger amounts of data and there is a tendency towards a greater variety of game images being represented. For example, configuration of each object is likely to become more complicated. The size of data for representing configuration and other object-related data used for each object is becoming larger. It is anticipated that the size of object-related data will become larger in the future.
As described above, in said conventional arts, the capacity of RAM required to execute a program for generating a plurality of objects is large. As a result, it has become difficult to secure RAM area for storing large amounts of data required for representing complicated object images. It is estimated that this problem will be more serious.
Therefore, the object of the present invention is to provide an object displaying method, a storage medium and a game apparatus using the above method appropriate to display a plurality of object images according to movement using a smaller capacity of the RAM.
In order to solve the problem described above, a game apparatus according the present invention provides a game apparatus for displaying objects in a virtual space at a predetermined period on a screen, comprising a storage means for storing movement information wherein a schedule from the generation to extinction of each of a plurality of objects of different types and movement pattern are defined, a judgement means for judging display timing of each object corresponding to the progression of a game by referring to movement information stored in said storage means, an acquisition means for acquiring the movement information of each object judged as being at display timing by said judgement means from said storage means, a physical simulation means for simulating the movement of each object in accordance with the schedule and movement pattern defined by the movement information acquired by said acquisition means, and a display means for displaying the image of each object in accordance with the movement simulated by said physical simulation means.
According to the game apparatus according to the present invention, by preparing movement information for each of the plurality of objects, it become possible to control the generation position of each object, whereby it becomes unnecessary to prepare a movement program for each object. As a result, it becomes possible to move the plurality of objects on a screen using a smaller amount of memory.
To be more concrete, the storage means stores the movement information including the generation position, direction of movement and amount of movement of objects defined as a movement pattern, said physical simulation means generates said object at a generation position defined by the movement information acquired by said acquisition means and calculates a position of said object at every predetermined cycle, in a case where said object is moved in a direction of movement defined by means of said movement information by a amount of movement defined by means of said movement information.
The object displaying method according to the present invention comprises an object displaying method for displaying a plurality of objects of different types in virtual space at a predetermined period on a screen includes a judgement step, wherein the display timing of each object is judged in response to the progression of a game by referring to movement information in which a schedule from generation to extinction and a movement pattern of the plurality of objects of different types are defined, respectively, a physical simulation step, wherein the movement of each object is simulated in accordance with the schedule and movement pattern defined by the movement information of the object which is judged as being at display timing in said judgement step and a display step, wherein an image of each object is displayed in accordance with the said movement which is simulated in the physical simulation step.
To be more concrete, in said movement information, the generation position, direction of movement and amount of movement of an object are defined as a movement pattern and in said simulation step, said object is generated at a generation position defined by said movement information acquired in said acquisition step, and the position of the object in a case where the object is moved in the direction of movement defined by said movement information by the amount of movement defined in the movement information is calculated at every said cycle.
The storage medium according to the present invention comprises a computer-readable storage medium stored with a program for displaying a plurality of objects of different types in virtual space at a predetermined period on a screen, wherein said program is programmed so as to make a computer execute a judgement step in which display timing of each object is judged by referring to movement information wherein a schedule from the generation to extinction and a movement pattern of a plurality of objects of different types are defined, respectively and a simulation step in which movement of each said object is simulated in accordance with the schedule and movement pattern defined by the movement information of said object which is judged as being at display timing, and display step in which an image of each object is simulated in accordance with the simulated movement.
To be more concrete, in said movement information, the generation position, direction of movement and amount of movement of an object are defined as a movement pattern and in said physical simulation step, said object is generated at a generation position defined by said movement information acquired in said acquisition step and the position of the object in a case where the object is moved in the direction of movement defined by said relevant movement information by the amount of movement defined in the movement information is calculated at every said cycle.
Another preferable embodiment of the recording medium relating to the invention is a computer-readable recording medium storing a program to be executed for a video game by a computer, wherein the program is commonly determined for a group of objects positioned in a three-dimensional space of a series of frame images displayed for the video game, and is programmed to execute an analysis step for analyzing time requirements, positional requirements, and image requirements relevant to at least display time, display positions, and images of said objects based on a plurality of parameters specified for the objects which specify a plurality of kinds of information to be commonly used for generation of the group of objects or used for generation of a part of images of the group of objects, a judgement step for judging display positions of the objects based on the positional requirements of the objects analyzed in the analysis step when judgement as to whether or not the objects should be displayed by frame images to be generated is made based on the time requirements of the objects analyzed in the analysis step in the case where the frame images should be generated and the objects are judged to be displayed, and a generation step for generating images representing the objects positioned at the object display position judged in the judgement step in accordance with the image requirements of the objects analyzed in the analysis step when the objects are judged to be displayed in the judgement step.
To be more concrete, in said judgement step, as for an object in said group of objects which is not displayed yet by a frame image generated immediately before said frame image to be displayed is generated, the object is judged to be newly displayed or not based on the time requirements of the object which has been analyzed in the analysis step, if it is judged to be displayed in said judgement step, a displaying position of the object is distinguished based on the positional requirements of the relevant object which has been analyzed by said analysis step, and as for an object in said group of objects which has been already displayed by the frame image immediately before the object, it is judged whether the object is designated to move or not by the positional requirements of said object analyzed in the analysis step, if said positional requirements of the object designates the object to move, a new displaying position of the object is determined based on the movement designated by said positional requirements and the position of the relevant object in a case when the object is displayed in said frame generated immediately before.
To be more concrete, in the judgement step, as for said object in said a group of objects, which has been already displayed by a frame image generated immediately before, it is judged whether the time requirements of the object analyzed in the analysis step specifies limited display duration of the object or not, and if said time requirements of the object specifies limited display duration, it is judged whether a display of the relevant object should be extinguished based on the limited display duration specified by said time requirements, and if it is judged to be extinguished, an image representing the object is not generated.
To be further concrete, steps from said analysis step to said judgement step are executed by a common part of the program for said group of the objects included in said program.
According to the present invention, if schedules and movement patterns for a plurality of respective objects are being regulated, unified control is enabled for respective objects, which makes it unnecessary to prepare movement programs for each object. As a result, a plurality of objects can be displayed with a smaller memory on the display screen.
The present disclosure relates to subject matter contained in Japanese Patent Application No. HEI 11-327554, filed on Nov. 17, 1999, the disclosure of which is expressly incorporated hereinby reference in its entirety.